What experience has anyone had with the Signatera blood test?

Turns out Mayo FL sends it to Mayo MN who send it to CA. Weird.

My 7/1 signatera is delayed. Mayo only sent the sample to Natera on 7/3. With the Holiday it may be delayed. It expires tomorrow 7/8. Annoying.

Signatera can be contradictory with Northstar Response so I would discuss the latter also. Although it is now explicitly no longer intended to be used in a predictive fashion.

I am not sure RBD will respond. I sent him two emails over the past few months and never received a response. Which makes sense as I am not his patient. But his research is very insightful.

Yes, thank you. We were up last night ironing out a decision-matrix based on PT scan, MRI, and Signatera values. And now our surgeon can reach out to Dr. Ben-David and compare notes after all the results are in. The plasmacytoid is a nasty spreader, often undetected in regular scans, so having the blood test as an extra back-stop is extremely comforting.

My Northstar Response from 2025-05-29 came back at 43. It is a new baseline. The test also has a new 10 to 400K scale. It added language that it should not be used to track MRD or early recurrence and only for solid visible disease. It is also more sensitive according to another patient who attended ASCO in person recently. Regardless, it came down from 130 on 2025-04-03 (the value would likely be considerably higher with the new assay) which indicates nivolumab efficacy. Such a decrease after two just two cycles is very encouraging.

Excellent. If you have high MRD on signatera before RC it may make sense skipping RC and proceeding directly with EVP.

Thank you for posting this. We just shared it with our doctors in order to inform our decision-making before the cystectomy.

Baptist MD Anderson called me today. My oncologist urologist there did TURBT 2. I saw him again for an update early last month. He consulted his peer and the PA called me today. Baptist MD Anderson would also have done DDMVAC and nivolumab. They do not do northstar and were unaware of it.

Liver enzymes came down. So either a resolving grade one irae or related to the liver iron deposit. We will check again before nivo 4 on 7/3.

Interesting research from JP on CBM588:
https://ascopubs.org/doi/10.1200/JCO.2025.43.5_suppl.774
https://pmc.ncbi.nlm.nih.gov/articles/PMC10778075/

Very interesting interview regarding signatera.
https://www.urotoday.com/video-lectures/aua-2025/video/mediaitem/4852-pre-cystectomy-ctdna-levels-and-metastatic-recurrence-in-bladder-cancer-patients-reuben-ben-david.html